Hartline, Green Bay's Jordy Nelson, Philadelphia's Riley Cooper, Detroit's Kris Durham, Denver's Wes Welker and Eric Decker, and New England's Julian Edelman and Danny Amendola are all flag holders for a position that is mostly manned by African Americans.

At one point white receivers were on the verge of becoming extinct like white cornerbacks, where Dustin Fox was the last white man standing opposite a receiver in 2008.

But in one season the number of white starting receivers has nearly doubled. And the present group, which features some elite talents like Welker and Nelson, are inspiring thousands of high school and college receivers who no longer fit the NFL's mold.

"Am I an inspiration?" Hartline ponders when asked about shattering barriers and NFL stereotypes. "I've always just stayed in my lane."

When told he's part of a dying breed of Caucasian skill players (receivers, tailbacks and defensive backs) which all happen to be positions that rely on speed, Hartline provided a Dikembe Mutombo-like block to the theory that stereotypes are keeping skill position players who look like him out the league.

"If they don't get the opportunity then they didn't deserve it," said Hartline, who will start his 51st NFL game against the Patriots on Sunday. "There is always an opportunity. Always! Opportunity is just hard work disguised."

In Hartline's world, more games are lost than won in the NFL. And the same applies to NFL jobs, and starting spots.

When Hartline joined the Dolphins back in 2009 the receiver unit was filled with unproven, unpolished players, including Patrick Turner, a former USC standout drafted a round before Hartline, who was taken in the fourth round.

Still, it didn't take Hartline long to work his way up the depth chart. Former Dolphins offensive coordinator Dan Henning declared Hartline the smartest rookie he'd ever coached, and it wasn't long before Hartline was leading the receiver meetings as a rookie.

He spent three years as the team's No. 3 receiver, biding his time playing behind and alongside Ted Ginn Jr., Greg Camarillo, Davone Bess and Brandon Marshall before opportunity knocked in 2012.

Despite missing all but two weeks of OTA and training camp practices because of an illness and an calf injury, Hartline took the field the week of the 2012 season opener and instantly became Ryan Tannehill's favorite target.

Last year he caught 74 passes for 1,083 yards and became the eighth Dolphins receiver to produce a 1,000-yard season.

Hartline points out everyone on that training camp roster had an opportunity to unseat him and cement themselves as a starter when he was sidelined. But when his time came he seized his chance. And that's been the story of his career.

This season he's caught 67 passes for 855 yards and four touchdowns, and is on the verge of becoming the fifth receiver in franchise history to put up back-to-back 1,000-yard seasons, joining Mark Duper, Mark Clayton, Irving Fryar and Marshall.

"There are opportunities. In this league the one thing that always prevails is the ability to play," Hartline said. "If it takes you too long to develop then that's your fault."

When he was a number three Hartline wasn't content with his status, but he understood.

"That's what I deserved," he explains. "If I was going to unseat a first-round pick (Ginn), or a guy who was more proven (Bess or Camarillo), then I should have done more. I didn't. The problem with the human mindset is that the opportunity you're given is never good enough."

Even despite the offseason addition of Pro Bowl receiver Mike Wallace, Hartline's crisp route running and quarterback-friendly approach has allowed him to remain Tannehill's favorite target. If that changes in the final three games, or the next three seasons, Hartline promises he'll still be content with what comes his way.

"Don't compare yourselves to other individuals and other paths only in a positive way. Factor in what it took to get there," Hartline said. "Don't just look at the outcome."